Railway car truck



Y W. J. HYMAN -RAILWAY CAR TRUCK Filed Feb. 24, 1933 Oct n 4Sheets-Sheet 1 ATTORNEY JNVENTOR WALTER J HYMAN.

Oct. 29, 1935. I w. J. HYMAN 2,018,854

RAILWAY CAR TRUCK Filed Feb. 24, 1333' 4Sheets -Sheet 2 a? IIIIIIIIP,I)I w. 22 a I7 18 FIG. 4. 'll/1111 Oct. 29, 1935. YMAN 3 2,018,854

RAILWAY CAR TRUCK Filed Feb. 24, 19 33 4 Sheets- Sheet 3 j/R///////////i 7 -V F 35 INVENTOR WALTER J. HYMAN.

' ATTORNEY Oct. 29, 1935. w J AN 2,018,854

RAILWAY CAR TRUCK Filed Feb. 24, 1933 4 Sheets-Sheet 4 III/III IIIIIIIII/fi INVENTOR Patented Oct. 29, 1935 UNITE STES This inventionrelates broadly to railway car trucks and relates more particularly tothe spring planks thereof and to the mounting of the spring planks inthe truck side frames.

Heretofore considerable difiiculty has been experienced in practice byreason of spring planks breaking transversely at or near their innerlines of support on the truck side frame or other supporting member; Thebreaks are believed to be due primarily to the weaving motion in thetruck when in service combined with the great downward pressure of thesprings, which pressure holds the ends of the spring planks againstmovement necessary to accommodate them to the weaving motion in thetruck. In certain instances, breaking is attributable also to weakeningof the spring planks adjacent the aforesaid inner lines of support byprovision of apertures for reception of lugs or other means serving toanchor the spring plank to the side frame or other supporting member.

The primary object of this invention is to provide means, applicable toexisting or to new construction, for anchoring or connecting springplanks to truck side frames or other supporting elements, with suchcapacity for movement relative to other elements of the trucks as willprevent concentration of stresses in the spring planks and fracture ofthe planks as aforesaid.

A further object is to provide means, applicable to new or to existingconstruction, for anchoring or connecting spring planks to truck sideframes or other supporting elements, the said means being of suchcharacter as will obviate the necessity of weakening spring planks, inthe region in which stresses have heretofore been concentrated, byprovision of apertures for reception of anchoring lugs or the like.

A still further object is the provision of a novel form of a springplank adapted to produce a novel operative relation of the planks,springs and truck side frames or other plank supporting elements, bywhich relation undesirable concentration of stresses in the springplanks is avoided.

Another object is to provide spring planks adapted to transmit load tothe truck side frames or other plank supporting elements always at ornear the central, longitudinal, vertical plane thereof and to preventthe transmission of load in suchwise as to create torsion stresses inthe side frame or other plank supporting element.

Another object is to provide spring planks accomplishing the foregoingand other objects and applicable to existing car trucks of appropriateplank and the side frames.

design without change in the trucks other than the substitution of newspring planks for old.

Still another object is to provide means for supporting and prolongingthe life of existing spring planks. 6

An additional object is to provide means as aforesaid of simple, durableand inexpensive character, capable of easy application to car trucks.

Various other objects and the advantages of 10 the invention may beascertained from the following description and the accompanyingdrawings.

The invention is capable of a number of embodiments whereby it isapplicable in a variety of ways to car trucks of various designs. Forpurposes of explanation, the invention will be described in itsapplication to a car truck of one well known design, but it will beunderstood the invention is not thereby limited to association with theparticular truck described or to the embodiments illustrated anddescribed, but embraces all such other embodiments and modifications asfall within the scope of the appended claims.

Broadly speaking, the invention resides in provision of means toestablish a rocking engagement between a spring plank and underlyingsupporting members, such as the tension members of truck side frames,and control of load transmission with reference both tothe supportingmembers and to the truck springs. The foregoing is accomplished eitherby provision of a spring plank having the under surfaces of its endportions which bear upon the truck side frames, or other supportingmembers, convexly formed thereby to permit a limited rocking relation ofthe spring plank and truck side frame in directions longitudinal and/ortransverse of the side frame, the said convex bearing surfaces 40 beingformed either integral with or separately from the plank proper; or byprovision of similar convex surfaces on the truck side frames-eitherintegral therewith or separately formed; or by provision of suchsurfaces on both the spring The convex formation of the bearing surfacesis such as to maintain contact with and load transmission to the truckside frame in or close to the central, vertical, longitudinal plane ofthe frame, thereby to avoid imposition of torsion stresses in the truckframe and concentration of bending and torsion streses in the springplank at locations materially inward from said plane. The inventionfurther resides in formation of the spring plank proper of strengthunimpaired at locations, spaced in wardly from said plane by provisionof apertures or recesses for co-operation with anchoring means on theside frame. In greater detail, the invention resides in the features andcombinations hereinafter or hereinbefore described or contemplated orillustrated in the accompanying drawings or falling within the scope ofthe claims.

In the accompanying drawings;-

Fig. 1 is a partial side elevation of a car truck of standard designillustrating the application thereto of a spring plank formed accordingto one embodiment of this invention.

Fig. 2 is a vertical cross-sectional view on the line 2--2 of Fig. 1.

Fig. 3 is a fragmentary vertical longitudinal sectional View on the line33 of Figure 2.

Fig. 4 is a fragmentary cross-sectional view on the line i@ of Fig. 1.

Fig. 5 is a horizontal sectional view on the line 5-5 of Fig. 1.

Fig. 6 is a bottom plan view of the bearing surface illustrated in Figs.1 to 5,

Fig. 7 is a section on the line 7-4 of Fig. 6.

Fig. 8 is a fragmentary vertical cross-sectional view, similar to Fig.4, illustrating a modification.

Fig. 9 is a view similar to Fig. 4 illustrating an embodiment of theinvention enabling use of existing spring planks.

Fig. 19 is a view similar to Fig. 2 illustrating a further embodiment.

Referring more particularly to the accompanying drawings, l l designatesone of a pair of similar one-piece cast truck side frames, and I2 aone-piece cast truck bolster, all of well known design. The side framescomprise the usual compression and tension members I3 and I4,respectively, and the columns 15 between which the bolster ends engage.In the type of side frame illustrated, the tension members each includea horizontal central portion l6, extending between the columns andcomprising outer and inner vertical webs ii and I8, respectively, and asubstantially flat top plate I9 which extends outwardly and inwardly ofthe webs and is supported by brackets 20. The plate I9 is normallyprovided with four upstanding lugs 2|, each surrounded by an annulargroove 22. A spring plank 23 is supported at its ends on the portions l6of the side frames. Springs 25 are arranged between the bolster andspring plank, a side bearing :25 being interposed between the bolsterand springs and a positioning plate 25 between the springs and springplank. The spring plate is held against slipping on the spring plank bydownwardly projecting lugs 2'! on the plate engaging in apertures 28 inthe spring plank.

According to this invention, the spring plank 23 (of which only one endis shown) is provided at each end, on its lower side, with a convexhearing surface 29, which engages the top plate IQ of the side frametension member. This bearing surface may be formed separately from thespring plank, as shown in Figs. 1 to a, or may be formed integral withthe spring plank as shown in Fig. 3, When dealing with alterations orrepairs to an existing truck, the convex bearing surface may be providedby interposing a rocker plate 3t between the existing spring plank andthe side frame tension member top plate [9, shown in Fig. 9,

the lower surface of the rocker plate being formed as hereinafterdescribed to provide the desired curvature. Alternatively, a new springplank may be inserted, as shown in Figs. 1 to 7, or the existing plankmay be reformed, as suggested in Fig.

8, or a new plank of this form provided. In dealing with existing trucksthe anchor lugs 2| may be allowed to remain or the two inner lugs may becut off. In the case of a new spring plank,

it is for some reasons preferable to form the bear- 5 matter of possibleconvenience or manufacturing -expediency and that the bearing surfacemay be,

and in some instances is preferably, formed integral with the springplank proper.

The convex bearing surface 29, whether formed integral with orseparately from the spring plank, 15 is preferably continuously curvedtransversely of the central vertical longitudinal plane of the tensionmember, which is indicated by the line 33 in Fig. 2, the curvature beingclearly shown in this figure. In the longitudinal direction of go thetension member, the central portion of the bearing surface is fiat andthe end portions only are curved, as clearly shown in Fig. 3.Theoretically, the surface curvature just described will provide a linebearing on the'tread plate I9 but 25 as the radius of the transversecurvature is considerable, there results in practice a contact surfaceof considerable width, as will be evident from Fig. 2. The normaleffective contact surface is roughly elliptical, as indicated in Fig. 6,The 30 lateral and longitudinal curvatures merge into one another and donot form sharply defined edges but rather a surface tending toellipsoidal curvature as shown by Figs. 6 and '7. The normal effectivecontact surface affords ample bearing 35 for transmission of all loadsto be dealt with and the continuous lateral curvature enables a smoothrocking relation between the spring plank and truck side frame uponrelative movement such as would vary the angle between the plane of the40 side frame and the plane of the spring plank. The curvature of therocker plate longitudinally of the truck provides for a rocking relationbetween the side frame and spring plank upon relative movement of thetwo resulting from oscilla- 45 7 tion of the side frame in its plane orfrom twisting stress applied to the spring plank.

The location of the bearing surface 29 relatively to the side frame issuch that the normal contact area of the bearing surface and the tread50 plate It is midway between the side frame webs l8 and midway betweenthe outer and inner rows of springs 2 3, so that the load isconcentrated along the vertical, longitudinal, central plane of the sideframe and equally distributed between 55 the outer and inner springs.The continuous lateral curvature is such that, upon the maximum changeof angle between the plane of the side frame and the plane of the springplank, the contact area of the bearing surface and tread 60 plate is notmoved wholly outside the outer web H nor wholly inside the inner web l8.Thus, the load is maintained in or adjacent the central verticallongitudinal plane of the side frame, and is not applied at the outer orinner edges of the plate I9 where it would set up torsion stresses inthe tension member and tend to break off the outer or inner extendingportions of the plate which are supported by the brackets 20.

The curved bearing surface 29, by maintaining 70 the load transmittingwithin the space 11-. its above defined, relieves the spring plank ofsevere bending stress, such as would occur at the inner edge of theplate l9 if the plank had a flat bearing on the plate entirely acrossthe latter. 75'

It will be apparent from Fig. 2 that as long as the load transmittingarea of the bearing surface 29 is between the outer and inner rows ofsprings, the spring plank is a lever fulcrumed between the springs whichare opposed to one another. The bending stress in the spring plank abovethe inner edge of the plate l9 is then-merely the unbalanced pressure ofthe outer and inner springs. This stress is much less than would resultat the same point if the spring plank had a flat bearing entirely acrossthe plate H], as the stress would then be the pressures of both outerand inner springs acting through their distance from the inner edge ofthe plate l9.

In a manner similar to that just described, the curvature of the bearingsurface longitudinally of the side frame ensures lower torsion stressesin the spring plank than would occur if the plank had a flat bearingacross its entire width on the plate is. The curvature of the bearingsurface 29 longitudinally of the side frame is not as important whenonly four springs are used as when the plank is widened, as shown inFig. 5, to accommodate six springs, but even with the narrower plankconsiderable reduction in torsion stress may be realized by curvature ofthe bearing surface for a relatively short distance inwardly from theedges of the plank.

The spring planks heretofore used with side frames of the formillustrated have been of the same plan contour as the spring plankillustrated in Fig. 5 and have been weakened seriously by provision ofapertures to receive the inner pair of frame lugs 25, as will beapparent from inspection of Figure 5. The weakening of the plank causesstrain due to torsion stress to occur at the point of weakness, and asthe line of weakness and strain is in such close proximity to the lineof maximum bending stress, over the inner edge of the plate l9, thecombined action of bending and torsion stresses causes fracture of theplanks along the line of weakness.

According to this invention, the spring plank is imperforate in theregion of former weakness and this in combination with the convexbearing surface ensures against acture as heretofore. One method ofavoiding undesirable apertures in the spring plank is the provision ofthe rocker plates 3%! beneath the spring planks and operativelyconnected thereto, either permanently or separably, by any suitablemeans such as an approximately centrally disposed upstanding lug 3! oneach plate engaging in an aperture 32 in the spring plank. The uppersurfaces of the plates are formed to conform to the lower surfaces ofthe spring planks so as to have extended engagement therewith and theplan profiles of the plates preferably correspond to the plan profilesof the plank end portions. The plates are provided with apertures 33 forreception of the frame lugs 2 l and these apertures may, if desired, besurrounded by depending flanges 34 entering the grooves 22 to ensure agreater depth of bearing against the lugs. The apertures 33 and flanges3 1 are so proportioned to the lugs 2! and grooves 22 as not tointerfere with free relative rocking movement of the plates 39 and l9.As long as the plate 352 and spring plank are connected, the plateapertures provide in effect merely recesses and any recessed formationof a bearing surface integral with the spring plank, serving the samepurpose, is to be regarded as merely a mechanical equivalent for thestructure illustrated.

In addition to enabling elimination of undesirable apertures in thespring plank, the plates 3i) afford support to the spring plank where itis subjected to the greatest stresses and, with a view to increasing thesupport thus afforded, the rocker plates are preferably extended somedistance inwardly of the inner edges of the frame 5 tension member topplates 99, as shown at 35 in Fig. 2.

Another embodiment of the invention is illustrated in Fig. 8 anddiscloses the convex bearing surfaces 29 formed integral with the spring1 plank proper.

scribed, is avoided by omitting apertures for the 15 1 inner pair offrame lugs. In applying a spring plank of this construction to anexisting truck, it will be necessary to cut off the inner pair of lugs,but in new construction, the inner pair of lugs may be omitted as shown,the outer pair being suflicient to hold the plank against sliding. Inthis embodiment, the spring plank, instead of being supported by anunderlying plate as. in the first described embodiment, is supported byan overlying plate 36 which may be formed with spring positioning means3'! and may thus replace the spring plate 26. The convex bearingsurfaces 29 may, conveniently, be formed by pressing portions of thespring plank from the plane of the remainder, thus providing a concaveupper sur- 30 face. In such case, the lower surface of the plate 36 willbe formed in conformity with the upper surface of the spring plank. Theplate may be permanently or separably attached to the spring plank.

Obviously, in constructions otherwise as illustrated in Figs. 1 to 7,the inner pair of lugs 2i may be cut off or, in new construction,omitted and the rocker plates formed without the inner pair of apertures33, as illustrated in Fig. 8.

A further embodiment of the invention is illustrated in Fig. 9 andpresents a modification of the rocker plates of Figs. 1 to '7 to adaptthem to existing spring planks, having apertures 38 therein forreception of the frame lugs 2!, the

modification consisting in providing the upper surfaces of the rockerplates with recesses 39 for reception of the downstruck flanges 40 onthe plank, which flanges are designed for entry into the grooves 22.ment may be formed for engagement with all four lugs 24 of the frame ormay be imperforate above the inner lugs, as shown; the lugs being cutoff and the inner flanges 40 of the plank flattened out. The rockerplate according to this embodiment, while it cannot repair the weaknessof the spring plank, afiords such support thereto and relief frombending and torsion stresses that the life of the plank will be muchlonger than if used without the rocker plate. The above supportingeffect will be materially increased if the rocker plates are permanentlyconnected to the spring planks as by riveting or welding.

In Fig. 10 there is illustrated a further em- 5 bodiment of theinvention according to which the convex bearing surfaces are provided onthe truck side frames. In this embodiment, as illustrated, a plate 4|,having its upper or bearing surface 42 curved similarly to the surface29 of the plate 30, is mounted on the top plate IQ of the side frametension member and held against sliding thereon by any suitable means,such as openings 43 receiving the side frame lugs 2i and,

if desired, flanges 44 around these openings en- The rocker plates ofthis embodi- 50 l tering the grooves 22 of the side frame. In order toreinforce an existing spring plank or a new similar plank againstbending under the concentration of load caused by the convex bearingsurface 42, a plate such as the plate 30 may be provided between thespring plank and the plate 4!, or the reinforcement may be effected bymeans of a flat surfaced plate 45 or by suitably stiff spring plate 26.Obviously, when new spring planks are provided, these may be ofsufllcient strength to enable elimination of additional plates, such asthe plates 3|] or 45. Any suitable means may be provided to hold theplates 30 or #55 against sliding on the plate 4!, for example, lugs M onthe plate 4| similar to the lugs 2| of the side frame and engaging inthe openings 38 in the plates 30 or in similar openings 46 in the plates45. Any suitable means, such as a lug s1 engaging in the plank opening32, may be provided to hold the plank against slipping on the plate 45,or the plate 45 may be welded or riveted to the plank. While the bearingsurface 42 has been shown and described as formed separately from theside frame, it will be obvious this surface 42 may be formed integralwith the side frame.

From the foregoing description, it will be apparent that, as comparedwith spring planks heretofore in use, the present invention provides formaterial reduction in the torsion and bending stresses in spring planksand that the invention is applicable to existing car trucks either as arepair or alteration to the spring planks or side frames thereof or byway of replacement of old spring planks with new planks embodying theinvention. While modification of the truck side frames by removal of theinner pair of anchor lugs 2| in existing frames, or their omission innew construction, is preferable, such removal or omission is notnecessary and these lugs may be dealt with as may be expedient in eachcase. It will also be apparent that the stress reducing features of theinvention may be realized equally by association of suitably formedseparate rocker plates with existing or new spring planks, or withexisting or new truck side frames, or with both planks and side frames,or by formation of the spring planks or side frames, or both, to provideintegral rocker bearing surfaces. In other words, the'spring planks andside frames may be either one-piece structures or composed of separableparts, as desired, the choice depending upon circumstances. For thisreason, in the claims, where the context permits, the plates 30 or 36and 4| are to be regarded as parts of the spring plank, or side frames,respectively, though not necessarily integral parts.

It will likewise be understood the invention is not limited to use withthe particular form of truck illustrated, particularly in respect of therelation of the spring plank to the side frame tension members, springsand anchor lugs, but extends to use with other forms of trucks and withother arrangements of springs and anchor lugs and other arrangements forspring plank support.

While the convex formation has been described as resulting fromprovision of curved surfaces, it will be understood the curvature is notnecessarily circular and that the convexity may result from provision ofa plurality of plane surfaces arranged at slight inclinations to oneanother.

Having thus described my invention, what I claim is:

1. A spring plank for railway car trucks having on the under side of itsend portions'convex bearing surfaces formed in their central portionswithout curvature transversely of the plank and curved between saidcentral portions and the edges of the plank. 5

2. A spring plank for railway car trucks having on the under side of itsend portions convex bearing surfaces continuously curved in thelongitudinal direction of the plank and substantially flat transverselyof the plank in the central l0 portion thereof and curved from saidcentral portion to the edges of the plank.

3. A spring plank for railway car trucks having convex bearing surfacesat its end portions on the under sides thereof, said bearing surfaces 15including a substantially fiat, substantially elliptical normal bearingportion, the major axis of which extends transversely of the plank.

4. A spring plank for railway car trucks having bearing surfaces ofsubstantially ellipsoidal 0 curvature on the under side of its endportions, the major axis of curvature being substantially greater thanthe minor axis thereof.

5. A spring plank for railway car trucks having on the under sidethereof at each end a bearlng 25 surface including a substantiallycentral, substantially fiat normal bearing portion, the maximumdimension of which extends transversely of the plank, and a surroundingbearing portion sloping upwardly from said normal bearing por- 30 tionlongitudinally and transversely of the plank.

6. A spring plank for railway car trucks having the end portions thereofof greater thickness than the intermediate portion and adapted forrocking engagement, longitudinally and transversely 35 of said plank,with an underlying supporting member.

7. A spring plank for railway car trucks having the end portions thereofof greater thickness than the intermediate portion, said end portionsbeing (0 formed to provide a substantially central. substantially flatnormal bearing surface, the maximum dimension of which extendstransversely of the plank, and a surrounding bearing portion whichslopes upwardly from said normal bearing 46 portion toward the sides andends of the plank.

8. A spring plank for railway car trucks comprising a body andseparately formed bearing plates disposed beneath and connected to theend portions of said body, the lower surfaces of said 60 plates being intheir central portions substantially fiat transversely of the body andsloping longitudinally and transversely of the body upwardly from saidcentral portions to the edges of the plates.

9. A spring plank for railway car trucks comprising a body andseparately formed bearing plates disposed beneath and connected to theend portions of said body, the lower surfaces of said plates beingcontinuously curved longitudinally 60 of the body, and having curvedportions extending transversely of the body from the edges part way tothe longitudinal axes of the plates, the lower surface of the platebeing straight, transversely thereof, between said latter curvedportions.

10. A spring plank for railway car trucks comprising a body andseparately formed bearing plates disposed beneath and connected to theend 7 portions of said body, the lower surfaces of said plates beingformed to each presenta substantially flat normal bearing portion, thegreatest dimension of which extends transversely of the body and asurrounding bearing surface which 75 slopes upwardly from said normalbearing portion to the edges of the plate.

11. In a railway car truck, in combination, truck side frames presentingspring plank seats and including upstanding spring plank anchor lugsdisposed eccentrically of said seats; a spring plank provided at itsends with convex bearing portions resting on said side frame seats andformed with upwardly extending recesses for reception of said lugs, saidrecesses being adjacent ,the peripheries of the bearing portions whereby.the central most used parts thereof are unim- .paired.

l2. In a railway car truck, in combination, truck side frames presentingspring plank seats and including upstanding spring plank anchor lugsdisposed eccentrically of said seats; a spring plank formed imperforatein vertical alignment with said lugs and separately formed bearingplates connected to the end portions of said spring plank and aperturedfor reception of said lugs, said apertures being adjacent theperipheries of the bearing plates whereby the central most used partsthereof are unimpaired.

'13. In a railway car truck, in combination, truck side framespresenting substantially flat spring plank bearings and each formed witha spring plank anchor lug projecting upwardly from said bearing anddisposed outwardly of the central, vertical, longitudinal plane of theframe and characterized by absence of spring plank anchor lugsprojecting above said bearing surface inwardly of said plane; and aspring plank having on the lower surface thereof at each end a convexbearing surface for engagement with said frame bearing surface andformed with a recess adapted to loosely receive the upwardly projectingframe anchor lug.

14. In a railway car truck, in combination, truck side frames presentingsubstantially flat spring plank bearings and each formed with a springplank anchor lug projecting upwardly from said bearing and disposedoutwardly of the central, vertical, longitudinal plane of the frame andcharacterized by absence of spring plank anchor lugs, projecting abovesaid bearing surface inwardly of said plane; and a spring plank havingat the ends thereof separately formed bearing plates adapted to rest onthe frame bearing surfaces, said plates having convex lower surfaces andbeing apertured for reception of the frame lugs.

15. In a railway car truck, in combination, side frames each includingupstanding spring plank anchor lugs disposed inwardlyv and outwardly ofthe central, vertical, longitudinal plane of the frame, a spring plankaperture-d for reception of said lugs and including underlying endreinforcing plates traversing the plank apertures in alignment withthese lugs which are disposed inwardly of said frame planes.

16. In a railway car truck, in combination, a side frame including outerand inner spaced vertical webs and a plate connecting said webs andconstituting a spring plank bearing; and a spring plank having a bearingsurface engaging the side frame bearing surface, one of said bearingsurfaces being substantially flat and the other of said bearing surfacesbeing curved in the longitudinal direction of the plank and providing anormal bearing portion adapted to normally engage said substantiallyflat bearing surface midway between the vertical planes of said webs,the curvature of said curved bearing surfaces being such that uponrelative rocking of the spring plank andside frame due to weavingmovement in the truck, the contact of the plank bearing with the framebearing will be maintained substantially between the outer verticalplane of the outer web and the inner vertical plane of the inner web. 5

17. In a railway car truck, in combination, a side frame and a springplank resting at its ends on said side frame, said plank and side framehaving engaging bearing portions one of which is substantially flat andthe other of which is curved 10 longitudinally of the plank, thecurvature of said bearing surfaces being such as to maintain thetransmission of load from the plank to the side frames in or adjacentthe central, vertical, longitudinal planes of the frames. 15

18. In a railway car truck, in combination, side frames each includingouter and inner spaced vertical webs and a plate connecting said websand constituting a spring plank seat; a spring plank including'bearingplates thereunder rest- 1) ing onsaid seats and extending inwardly fromthe inner edges of said seats, the lower surfaces of said plates beingcurved in the longitudinal direction of the plank in suchwise as tomaintain the contact of said plates with frame seats spaced B5 frame anda spring plank resting at an end on U said side frame and outer andinner springs resting upon the end of saidplank, said plank and framehaving engaging bearing surfaces one of which is substantially fiat andthe other of which is curved in the longitudinal direction of the aplank, the curvature of said curved bearing surface being such as tomaintain the load transmitting contact of the plank and side framesubstantially between the vertical axes of the outer and inner springsabove said bearing surface during relative rocking of the plank andframe due to weaving movement in the truck.

20. In a railway car truck, in combination, side frames and a springplank resting at its ends on said side frames and outer and innersprings 45 resting upon each end of said plank, said plank including atits ends separately formed underlying bearing plates convexly curved ontheir lower surfaces in the longitudinal direction of the plank insuchwise as to maintain their load transmitting contact with the framessubstantially between the vertical axes of the outer and inner springsabove, said plates extending material distances inwardly of said innersprings.

21. In a railway car truck, in combination, 55 side frames and a springplank supported at its ends on the side frames, the contacting surfacesof said frames and plank being formed to provide rocking bearings forthe spring plank adapted for rocking movement in directions longitudinaland 60 transverse of the plank.

22. In a railway car truck, in combination, a side frame member and aspring plank member, one of said members having a convex surface 65curved longitudinally and transversely for engagement by the othermember which is substantially flat thereby to provide rocking engagementof the members.

23. In a railway car truck, in combination, a 70 side frame member; aspring plank member; and a bearing plate interposed between said membersand formed with a convex surface rockingly engaging a substantially flatportion of one of said members. 76

24. In a railway car truck, in combination, a side frame having a convexbearing surface curved longitudinally and transversely of the frame anda spring plank engaging said convex surface and formed to have freerocking engagement therewith.

25. In a railway car truck, a side frame having a convex spring planksupporting'surface curved longitudinally and transversely of the frameand adapted for free rocking engagement with a spring plank.

26. A spring plank bearing plate formed with an opening to receive ananchor lug and with a convex bearing surface, said opening beingdisposed within the periphery of the bearing surface and eccentricallyof said bearing surface whereby the central, most used part of saidbearing surface is unimpaired.

2'7. A spring plank bearing plate having one surface thereofcontinuously curved. in its longitudinal direction and in its transversedirection curved from the edges part way to the central longitudinalaxis and straight intermediate said latter curved portions.

28. A spring plank bearing plate having one surface thereof curvedlongitudinally thereby to enable relative rocking engagement with acomplementary member, said plate being apertured on one side of itstransverse axis for engagement with anchoring lugs and being imperforateon the opposite side of its transverse. axis.

29. In a car truck, in combination, a side frame including a springplank seat. a spring plank and a bearing plate interposed between thespring plank and said seat and adapted for movement relatively to theside frame when in service, interengaging means on said seat, plank andbearing plate whereby the plankand bearing plate are heldagainstmovement in their edgewise direction relatively to the sideframe,said interengaging means being freely' separable upon such limitedrelative vertical movement of the plank and side frame as may beeffected without dismembering the truck and permitting removal of theplate in its edgewise direction, one

of said seat and plate having a convex bearing WALTER J. HYMAN. U

